How to declare pointer?

[zybCM4Gy]

I simply want to know what is the right way of declaring a pointer.

    int *ptr1; //This is vulnerable.
    int *ptr2 = 0; //This is wrong. 

Mostly because I keep getting "warning: zero as null pointer constant". Which means that it's not entirely legal and I'm not certain whether I should initialize it as null or nullptr.

Yes I'm using C++11.

Thanks

[zybCM4Gy]

Interesting C++98 is a little bit difficult here, so I'm not sure how I should declare a pointer in C++98 but I am sure in C++11.

In which case a ptr should be defined as

    int *ptr1 = nullptr;

Sauce: https://stackoverflow.com/a/7016898

[Peter87]

Note that it's a warning, not an error. The warning can probably be disabled in your compiler.